This invention relates to a magnetic recording tape driving apparatus and, more particularly, to a magnetic recording tape driving apparatus, which has two pairs of reel shafts with each pair of reel shafts driving a magnetic recording tape in a cassette tape.
The magnetic recording tape driving apparatus noted above is well known in the art, as disclosed in Japanese Utility Model Disclosure No. 53-73809.
In the magnetic recording tape driving apparatus disclosed, two head base plates are provided for respective pairs of reel shafts, each head base plate carrying a magnetic head and a pinch roller. The two head base plates are operated independently in correspondence to various modes of the magnetic recording tape driving apparatus. With this construction, an operating means for operating the two head base plates independently is complicated in construction, leading to a complicated construction of the overall apparatus and hence to increase of the costs of manufacture and assembly and increase of the size of the apparatus.
Further, in the prior art magnetic recording tape driving apparatus disclosed, the two pairs of reel shafts are driven by a single motor as a power generating means. This structure, unlike the case where two separate rotational power generating means are employed for driving the two pairs of reel shafts, can be free from a rotational power transmission mechanism for transmitting rotational power from one rotational power generating means to one of the two pairs of reel shafts as well as that rotational power generating means, so that the construction of the apparatus can be simplified, leading to reduction of the costs of manufacture and assembly and also to reduction of the size of the apparatus. However, in the prior art apparatus noted above belts are employed for the transmission of rotational power from the motor to two pair of reel shafts. The belts are liable to become loose or be excessively stretched with temperature changes, leading to slip or excessive friction. In such cases, it will become impossible to obtain accurate transmission of the rotational power and drive the mangnetic recording tapes in the two cassette tapes at a predetermined speed.